Advances in care of patients with sickle cell disease (SCD) and early diagnosis through newborn screening have reduced mortality and morbidity. Correspondingly, the high risk status of patients with SCD for subtle cognitive and learning deficit and psychosocial developmental problems is becoming clear. However, good adjustment is also possible. Theoretically and conceptually driven studies are now needed to delineate how biomedical and psychosocial processes act together in normative vs. problematic adaptation to SCD. This developmental follow-up project is guided by an integration of components of conceptual models that emphasize the role of the cognitive processes of stress appraisal and causal attributions and methods of coping with stress and pain in mediating the illness-outcome relationship. Study I extends the follow-up of the patients enrolled in the current project and has two objectives: (1) to assess the impact on psychosocial adjustment of movement through a developmental transition; and (2) to include assessment of vocational adjustment, psychological adjustment through structured clinical interview, and mediational processes based on the learned helplessness model. Study II is a developmental follow-up of the Newborn Screening Program and has two primary objectives: (1) to evaluate the impact and effectiveness of the program; and (2) to longitudinally assess the cognitive and psychosocial development of the newborn screening cohort and delineate the development of processes hypothesized to mediate maternal and child adjustment. Both studies utilize a within group, longitudinal follow-up design. The potential contribution of this project lies not just in documenting cognitive and psychosocial outcome associated with SCD. The underlying conceptual models offer the potential to generate knowledge that can influence care by identifying patterns of individual and socioecological processes that place development at risk and that constitute salient targets for specificity of intervention efforts.